CAI and remove CAT - How much horse power?
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Re: CAI and remove CAT - How much horse power?
a few years ago one of the import magazines did a test on the power difference between a stock cat, a high flow cat, and a test pipe (no cat). the vehicle they tested was an already highly tuned R34 skyline. the baseline test, with the factory converters, was somewhere around 540 whp. the high flow cat gained i think 2 hp. the test pipe only gained another 3 or 4.
on a race car, that can matter. on a stock or mostly stock civic, that's more legal and environmental risk than is worth the reward of 1-2 hp. your car would be noticeably louder, even with a factory exhaust. modern oem catalytic converters do not restrict flow a significant amount.
see my sig, my 242 turbo made more "butt dyno" power with a factory cat and a straight through muffler, than with no cat and a stock muffler. it was quieter that way as well.
on a race car, that can matter. on a stock or mostly stock civic, that's more legal and environmental risk than is worth the reward of 1-2 hp. your car would be noticeably louder, even with a factory exhaust. modern oem catalytic converters do not restrict flow a significant amount.
see my sig, my 242 turbo made more "butt dyno" power with a factory cat and a straight through muffler, than with no cat and a stock muffler. it was quieter that way as well.
Last edited by turbo zombie; Nov 1, 2009 at 11:25 PM.
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Re: CAI and remove CAT - How much horse power?
you cant really do anything to your stock d17 ecu, you could buy a piggy back ems or hondata kpro, but if you dont have any big plans for the car, or plan on spending a decent amount of money then it wouldnt be worth it
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buy a FD2 SI and add a FD2-R spoiler to it and a few other upgrades.
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Re: CAI and remove CAT - How much horse power?
I honestly don't think you need to be messing with cars. You first made a post about removing your cat and adding an intake instead of searching. Now you want to sell it and buy another car, and the first thing you want to do is put on a spoiler and other nameless random mods. Pardon my French but **** the spoiler and save up your money for something worthwhile like a turbo kit. You came asking about power gains and now you want to buy a new car and put a spoiler on it. If the reason you are selling your car is a lack of power, buy parts that will add power to the new one and buy your spoiler later.
Last edited by ProjectMayhemR; Nov 4, 2009 at 12:57 PM.
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NA needs at little back pressure. It really Helps when using on a Turbo car. Turbochargers them self create the back pressure that's needed. Removing you cat isn't going to allow you to gain too much from a d17.
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I honestly don't think you need to be messing with cars. You first made a post about removing your cat and adding an intake instead of searching. Now you want to sell it and buy another car, and the first thing you want to do is put on a spoiler and other nameless random mods. Pardon my French but **** the spoiler and save up your money for something worthwhile like a turbo kit. You came asking about power gains and now you want to buy a new car and put a spoiler on it. If the reason you are selling your car is a lack of power, buy parts that will add power to the new one and buy your spoiler later.
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Registered!!
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I honestly don't think you need to be messing with cars. You first made a post about removing your cat and adding an intake instead of searching. Now you want to sell it and buy another car, and the first thing you want to do is put on a spoiler and other nameless random mods. Pardon my French but **** the spoiler and save up your money for something worthwhile like a turbo kit. You came asking about power gains and now you want to buy a new car and put a spoiler on it. If the reason you are selling your car is a lack of power, buy parts that will add power to the new one and buy your spoiler later.
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guys talk to bomber and he will tell u no cat WILL give you power. All this talk of backpressure is just crazy. you can run 2.5" exhaust on all stock with no cat and STILL have more than enough backpressure. I run 2.25" on pnp head with stage 1 cam and before i put a header on i was running stock exhaust and there was SOOOO much backpressure my header cracked and the crack expanded to a hole. Just an fyi. Our cars have so much backpressure u dont neet to worry about it. Cat is terrible for the environment I will admit and for personal reasons i will probably add a cat but for now its really not that bad. Loss in backpressure is insignificant when compared to the butt dyno results
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Re: CAI and remove CAT - How much horse power?
how come all these 200+ hp cars all have cats from the factory and run just fine? but on a civic with 100 hp it causes problems.
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FD2 is only type r. SI is FA5 for the sedan and FG2 is the coupe so i think you want to go for the type r look.
Last edited by 2005civiclx; Dec 23, 2009 at 12:44 AM.
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